


Festive Family Fun

by MeGaLoTrash



Category: Undertale (Video Game)
Genre: Bottom Papyrus (Undertale), Conditioning, Daddy Kink, Dubious Consent, Fontfest - Freeform, Hypnotism, M/M, Manipulation, Multi, Praise Kink, Restraints, Tentacle Dick, Tentacle Sex, Threesome - M/M/M, vaguely festive
Language: English
Status: Completed
Published: 2017-12-13
Updated: 2017-12-13
Packaged: 2019-02-14 08:58:55
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 6,131
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13004310
Author URL: https://archiveofourown.org/users/MeGaLoTrash/pseuds/MeGaLoTrash
Summary: Serious note: This is dubcon in places, though consent is acquired later- it's questionable at best, and manipulative. Please mind the tags.Happy holidays! This is a Fontfest fic that kinda spiralled out of control XDAu-ish,  still the classic UT setting but Sans and Papyrus live with Gaster at the Hotland labs instead of Snowdin... That and Gaster isn't in the void obviously :')Hope you enjoy!





	Festive Family Fun

Gaster allowed himself a rare moment of letting his emotions show by letting out a heavy sigh. Soft, barely there whimpers were travelling through into his sleeping quarters, interrupting his scheduled sleeping time. He was a patient man, and he would usually be content get out of bed and grab himself a refreshment until the noises faded away. But this ‘problem’ was becoming more frequent, this was the forth time he’d been woken up this week alone. While he didn’t want to interfere with his son’s private time, the fact that it was impacting both of their sleeping schedules so heavily was not acceptable.

He had realised long ago that his eldest Son, Sans, had an almost overwhelming attraction to his brother Papyrus. Gaster didn’t mean to eavesdrop, but the walls in between their sleeping quarters weren't thick and he often heard Sans calling out for his brother in the throws of passion. Normally he would have been content to let something of this nature ride its natural course. But he had no way of knowing how certain factors of their current situation were going to play out, considering how unique to them it was. He was aware that familial attraction was uncommon, and considered taboo amongst many, but neither of his boys were conceived in the traditional sense.

Considering his lack of a compatible partner, Gaster had created his ‘sons’ using his own magic and matter. They were considered brothers in a lot of ways, but Gaster found it fascinating how they were drawn together. Even Papyrus who currently showed little to no sexual interest, loved Sans with all of his being. The younger skeleton would insist on being close to Sans at every given opportunity, fussing over him whenever Gaster and Sans finished their work for the day. Although he was currently going through rigorous training in order to be considered for the royal guard, Papyrus always had boundless energy for his brother, but the line was drawn at platonic interaction. Sans was Spiralling as his attraction deepened, but he lacked a proper outlet to deal with his frustrations.

Gaster would have gladly offered his own companionship for relief, but he doubted such a clinical proposition would be accepted. It wasn’t that Gaster didn’t feel attraction, despite himself he also felt an unexplainable pull towards them both. But it would feel too forced when he knew how much his Sans ached for his younger brother. He also didn’t want to embarrass his son by acknowledging the attraction when Sans went to such lengths to try and hide it.

The scientist sighed heavily again as he pushed himself up from his bed, resigned in his fate of not getting any more sleep until Sans was done. He couldn’t complain; he may have been having sleeping issues but Sans was going through so much worse. He slowly opened the door to his bedroom, careful not to bump his head on the ceiling or make a sound. When he had first moved into the lab’s quarters he had realised they were more suited to monsters of average size quite quickly after more than a few mild concussions. He started making his way down the hall to the kitchen as he pondered his situation. He knew he needed to come up with a long term solution, but that was something for his fully conscious brain to deal with.

A small noise coming from further down the hall made him pause. He could still faintly hear Sans, but it was the early hours of the morning and there shouldn't have been anything else causing a stir. He looked along the blandly decorated hall to find the source of the noise, perturbed that he hadn’t noticed the faint light coming from one of the rooms until now. Gaster realised he was more tired than he thought, his usual perception out of sync due to lack of sleep. But now his interest was peaked; that was definitely Papyrus’s door that the light and faint sounds were coming from. Gaster was thankful for once that his son had no sense of boundaries, his door was open just enough that he could peek inside without alerting the other of his presence.

He wasn’t exactly sure what he expected to find, but it definitely wasn’t the vision of his youngest son thrusting his whole body against his pillows on the cot.

Gaster felt his usually stoic expression flush, he couldn’t deny that seeing someone he perceived as so innocent was making his own magic behave erratically. He stuck to the shadows and watched as his offspring quickly humped his way to completion, his own hand wandering dangerously close to his own nether regions. When he heard Papyrus call out for his brother though, Gaster found it hard to contain his trill of glee before he slipped off back to his own quarters.

It was too perfect. This wasn’t some one sided crush like he thought, his sons were both pinning for each other.

But why were they holding back when it was so painfully obvious they would make each other happy? Gaster speculated that the fact that society didn’t exactly take kindly to inter-familial relationships was holding them both back. Considering their conception, it seemed only natural that they would be drawn together in more ways than one. But fear was stopping both of them from even daring to test the waters. Gaster was pretty sure it was going to stay that way until feelings of repulsion pushed them apart… unless he intervened.

A plan started to form in his mind over how he could manipulate certain circumstances in order to make their coupling a success. As soon as he was back in his quarters he was at his desk and brainstorming. A normal confession had a low probability of succeeding considering the internalised shame both of them likely carried. Gaster concluded he would have to be more overt, exposing the raw desire they had for each other would leave less room for any doubts to fester.

He was happy with his method, but he came up against a few hurdles when he was figuring out how he could execute the plan. Normal social conventions dictated then his sons would not find each other in such states under every day circumstances… but that was where he could come in. An idea struck him, and Gaster almost smacked his forehead from not thinking of it sooner. Long ago, when his creations were new and unstable he had used his powers of suggestion to instil trigger words into their psyche. It was so he could carry out thorough tests without fear of his sons hurting themselves or anyone else. While many at the lab were convinced he used magic to restrain them, it was merely hypnosis techniques he had picked up when studying different human practices. It was less intrusive than magical restraint, and it worked perfectly on such impressionable minds.

Gaster hadn’t used such techniques for years, but he was certain the triggers would still be active. As his sons were so different, he had developed separate parameters for them both. Sans had triggers that would knock him out cold, but Papyrus worked better in a semi-conscious and suggestible state. A smile worked onto his face as he started to think of a plan involving these new revelations. Gaster could convince himself he was doing all of this for the sake of productivity or wanting to see them happy, but he couldn’t help feel excited as he plotted his involvement. It wasn’t exactly ethical...but if it was a successful experiment then the results would far outweigh it’s dubious morality.

As he started to jot down a time line of events, figuring out how he could excuse them all from their duties for a few days, he couldn’t help but think of his interference as a gift… it was the holiday season after all.

It took Gaster just over a week to make sure he was ahead enough on his work to be able to close the labs, and to be able to make the arrangements for their time off together without either of his sons knowing. Gaster really enjoyed this time of year; no one questioned that he was being secretive, and it even inspired him to acquire a few choice items that would enhance his plans. Once he had done all the prep work all he had to do was wait until the evening when the labs would clear out and they could finally be alone. Although he knew there was still margin for error, he couldn’t ignore the soft tingling of magic that lingered inside him throughout the day.

As the evening drew near, Gaster was pleased that both of his sons found their way into their living quarters. He walked into the room with a sly smirk on his normally neutral features. The scientist had set up the devices he had borrowed from the labs in plain view, but since the moving of equipment was such a frequent occurrence neither of his sons paid the bulky apparatus at the back of the room any mind. Sans was already falling asleep in the worn couch, and Papyrus was sat next to him with his face buried in the advanced puzzle making book Gaster had given to him as an early giftmas present. Even before he had set his plan in motion the brothers were snuggled together close, Sans had his legs propped up on the couch and was just barely touching Papyrus as he was hummed happily. Gaster paused before approaching, the scene before him was a picturesque representation of everything he cared about.  
But it was time to set his plan in motion.

Although Sans seemed to be losing consciousness, Gaster wanted to make sure his eldest son wouldn’t interfere with his plans until he was ready. He grabbed a blanket from the nearby storage unit and placed it over his son in what would appear to be an affectionate, fatherly gesture. He leaned in like he was going to give Sans a kiss on the forehead so Papyrus didn’t become suspicious and whispered the trigger that would knock Sans out cold. His smirk grew further when Sans’s body became lax, the old trigger being a complete success.

Gaster manipulated his eldest son’s body until there was enough space on the couch for him to sit down next to Papyrus, pleased that he could now focus all of his attention on his youngest son. “Are you enjoying your present Papyrus?”

“Yes! There Is So Much To Learn I Can’t Read It Fast Enough!” Papyrus beamed before folding the book on his lap and turning towards his father “Thank You So Much For Such A Thoughtful Gift, I Can Only Hope You Will Enjoy Mine Just As Much!”

“I’m sure i'm going to love it, whatever it is” Gaster moved his hands towards Papyrus, noting how they slightly shook as he prepared to make the move that would put him in full control of the situation. He also noted that he wasn’t sure whether his physical reactions were from nerves over doing something he shouldn’t, or excitement. As he made sure Papyrus was making full eye contact with him he concluded it was probably both.

“You really are one of my favourite creations”

Papyrus’s eyes went wide before becoming hazy, a clear sign that Gaster had managed to trigger his docile state. Gaster waved his hand in front of his son's face to test his reactions, pleased that Papyrus followed his every move. He pushed aside the guilt he felt upon seeing his usually jittery Son turn into putty as he lead him over to the nearby examination table. Gaster had already adjusted it into a perfect position this morning when he moved it into their living room; the back was pushed up so Papyrus would be in a semi sitting position and the stirrups had been adjusted for his son’s height. Just thinking about seeing Papyrus spread out on his apparatus was making Gaster’s magic twist around his body, seeking formation. He quelled his desires for now, knowing that his patience and attention to detail would eventually reward him.

“Strip, and form you’re preferred ecto-body when you’re done”

Gaster was facing away from Papyrus when he gave the order, wanting to retrieve a few things he’d hidden in a nearby storage unit before they started. But the scientist still felt a shiver of pride when he heard Papyrus’s clothing dropping to the floor, he really had trained his son well all those years ago. From previous observations Gaster knew Papyrus could form a more feminine body but he wasn’t prepared for the feeling of seeing him completely nude and exposed when he turned around.

Papyrus didn’t show an ounce of shame or try to hide his body. It wasn’t part of his programming in this relaxed state, and Gaster silently thanked his past self for such a wonderful inclusion. He was able to observe his son’s sculpted body without obstruction, making a mental note to praise him on how much his physique had improved. Even though his curves were soft it was obvious Papyrus was in good shape, and the magic that made up his body swirled so tantalisingly that Gaster found himself walking over to where his son was stood without really meaning too. Papyrus just looked so good, and he was stood completely still, almost like a doll you'd find in a shop window. And dolls were meant to be played with.

“Good boy” Gaster trailed a hand over the front of his son’s body, stopping to cup at one of the pert breasts on his chest “You’re such a good boy aren’t you Papyrus? Speak”

It took a little while for Papyrus to respond, his breathing was already laboured from the light stimulation. But when he did his voice came out slow and precise, just like he had taught him. “I Am A Good Boy...Daddy”

Gaster felt a shiver go up his spine, he hadn’t expected the effect that that word would have on him. He knew Papyrus had favoured that term of endearment in the past, but it carried a whole new meaning now. The scientist knew he was becoming more aroused than he planned from the situation. But the combination of Papyrus's submissive state, his tone of voice, and the fact he could get Papyrus to do whatever he wanted was pushing all of his buttons. He had kept his hand on Papyrus's chest but he decided to reluctantly draw back so they could move forward with his plan.

This set up wasn’t for him, he was meant to be the facilitator.

“On the bed Papyrus, and place your legs in the stirrups please”

Papyrus did what he was told faster this time, though Gaster did detect a hitch in his breathing when he opened his legs fully on the apparatus. The scientist knew that under normal circumstances his son wouldn't be willing to expose himself so much without a lot of persuasion, so it was reassuring that some of Papyrus's traits were present even now. He wanted to lower inhibitions with this exercise, not force anyone to do anything they wouldn't want to do. A quick glance towards Sans's sleeping form reminded him that his eldest son probably wouldn't be as co-operative when he was awake. Even if Gaster knew it was what he wanted, Sans was so strong willed it would take more than suggestion to break him. Which was why the next part of his plan needed to be executed with care.

Now Papyrus was in place, Gaster needed to focus on both preparation and presentation. The preparation wouldn't be too difficult, in fact the scientist was confident it would be enjoyable for them both. But the presentation... He had set up a chair to prop his eldest son up at an angle where he would be able to observe Papyrus intimately. But he was a little hesitant when it came to the rest of the presentation. Papyrus needed to be secured in the stirrups for the best results, but Gaster was in two minds about how to restrain him. He had bought the festive ribbons and bows on a whim, but now as he was cutting lengths off it seemed a little on the nose. But the thought of Papyrus all wrapped up like a giftmas present was an even more tempting image now he had seen his son nude. Plus, If Gaster thought the image was erotic, he knew Sans would be foaming at the mouth.

Papyrus's breathing was uneven when he started, but it became more like panting as he worked. Gaster went for the practical ties first with the thicker ribbon, and he heard his son hiss in pleasure as the soft material grazed over the sensitive skin of his legs. The ties held his legs in place effectively, but they could be easy loosened if Papyrus wanted to. His job was to make sure the thought of escape didn't even cross his son's mind. With the base ties done, he started to work more decorative ties that would accentuate Papyrus’s best assets. Although he had originally had doubts over the ribbon being in such a deep red, it actually complimented the striking orange of his son’s magic quite well.

But he didn’t just want Papyrus to look good, he wanted him to feel good too. Though Gaster had been saving touching his son’s more sensitive areas until the practical ties were done, Papyrus was already worked up enough that his opening had started to lubricate itself. The scientist could see why his son preferred such a form more clearly now; every little touch or brush against any of his exposed flesh seemed to send a current of pleasure straight to the mound between his legs. Gaster could feel his own magic eager to form in response to such a delicious sight, and now he was nearing the next part of his plan he was happy to let it happen.

Now that the intricate work was done, Gaster slowly let his magical tendrils take form and slither their way around the table to assist him. The swirling mix of the deep purples and blacks that made up his magic made Papyrus look even more exquisite by comparison. He started to wrap ribbon around Papyrus’s breasts so they would appear more prominent as two of the tentacles stimulated each of his nipples until they turned hard. Papyrus’s lack of modesty in this state meant he didn’t even think to hold back the endearing whimpers of pleasure as Gaster caressed him with multiple appendages. His son arched his back for more, his hands twitching as he held back from touching himself where he needed it most. While Gaster would have loved to watch Papyrus come undone from his own touch, he needed to make sure his son was brought to the edge of climax. Release would come later when his brother was involved. 

Satisfied that Papyrus looked like the perfect present, he went to retrieve Sans so he could put him into position. Summoning more tendrils took little effort with how much excess magic Gaster’s body was producing in its heightened state, and he used them to restrain Papyrus’s arms for now and finally give his slick pussy some attention. He almost dropped Sans as he was carrying him over to the chair, the warm and wet sensation from just caressing the outside of Papyrus’s sex was overwhelming. And the noises… Papyrus’s voice was unrestrained and heavy with arousal, he probably wasn’t far off his first climax already. The urge to plunge inside as he teased his tendrils around the dripping folds was almost too hard to resist, he had to take a moment to compose himself as soon as he placed Sans on the chair. 

Gaster’s patience for holding back may have been wearing thin, but if he just held out a little longer his preparation wouldn’t be for nothing. He would be able to feel that wet heat wrapped around him and hear the sweet sounds only grow in volume. But he needed to tease him into more of a frenzy while he worked on restraining Sans. Gaster knew his eldest son’s first instinct would be to run and protect Papyrus no matter how obvious it was that he was enjoying himself. But he didn’t want to restraint Sans permanently, considering how he hoped he would eventually be unable to resist his brother’s calls. So he settled on wrapping a few thick tentacles to bind Sans to the chair and one more to linger close to his crotch. 

His grand reveal was almost ready, Gaster just needed to prepare the finishing touches. He brought a separate chair for himself to position right behind Sans. He had originally thought about sitting off to the side, but in this position he could feed suggestions to Sans and make him give into his desires. The full frontal view of Papyrus was an added but more than welcome bonus. The scientist made minor adjustments to Sans’s sleeping form while driving Papyrus closer and closer to the edge. With some minor concentration Gaster managed to split some of the tentacles stimulating Papyrus into multiple strands, wrapping them around his still erect nipples and using one to stimulate the bundle of nerves at the top of his sex.

The reaction was instant, Papyrus only stopped moaning now to take shallow breaths and his pitch was shifting even higher than before. Gaster decided he was done with teasing, leaning forward in his chair to click his fingers loudly to snap Sans out of his slumber. 

His son was groggy at first, as if waking up from a nap, but when Papyrus’s cries reached him he immediately snapped to attention. Gaster watched as his eldest’s eyes went from wide with alarm to a mix of confusion and arousal when he saw the sight in front of him. The fact that Sans was only a few feet away from his brother’s open legs, with his gaze perfectly in line with that delicious pussy, was all part of his plan. It was so well executed that he was almost offended when Sans tried to struggle against his bonds. 

“Ah-ah” Gaster teased, trying to keep his tone light even though his own arousal was obvious in his voice. “Not just yet. I want you to watch first Sans” 

Sans was about to speak but a needy cry from Papyrus cut him off. Gaster had begun teasing a tendril just out his entrance and the moans and whimpers on a new layer of neediness.Papyrus hadn’t been given permission to speak again, but Gaster wasn’t even annoyed when he heard small pleas mixed in with his moans. They just added an extra flavour to the situation, and would surely be getting to Sans even through his misplaced rage. 

The smaller skeleton was still struggling though it wasn’t with as much blind panic as before. Still he did lean his head back to where Gaster was sat to whisper at him vehemently “i don’t know what the fuck you’ve done to him ‘dings, but this isn’t-”

“Hush now, i’ve not done anything to alter his desires- i’ve simply put him in a more suggestive state-” Gaster let his own tone drip like honey, watching as his eldest son shivered despite himself. Clearly Sans was affected by auditory stimulus, perhaps even more than visual. Gaster decided to use that to his advantage. “Just listen.. Papyrus do you want this?”

“Yes! Please, I Want It! I Can’t Wait Any More!”

Sans stilled his struggling at that as his face snapped in Papyrus’s direction, clearly entranced by such a direct confession. Gaster couldn’t stop himself from making more pleased sounds, not now all the pieces were all slotting into place. From his position Gaster could hear his eldest son’s breath becoming laboured and he noticed the bright blue of his magic forming in his shorts. The scientist wasn’t surprised Sans was responding so soon, he knew how often the smaller skeleton fantasised about seeing his brother like this. Still his quicker compliance made this part easier, he wanted to make sure Papyrus was fully conscious before he penetrated him. He may have been willing build up in a gray area of morality, but this felt like a line that everyone would regret crossing without consent. 

“Good boy Papyrus, you really are one of my favorite creations…” Gaster held his breath as he repeated the trigger, breathing a sigh of relief when Papyrus’s eyes only widened slightly before he went back to moaning for more. “But I want you to do something for me-”

Papyrus cut him off with another long whine as he tried to gain some friction with his hips “Nyeh- I Need Ah! I’ll Do Anything Daddy” 

Gaster spluttered despite his efforts to remain calm, he would have never thought Papyrus would say that in his right mind. But he realised his youngest son was completely full of surprises as he tried to wiggle himself down onto the long tendril resting just outside of him. Gaster hadn’t intended on having this much fun himself, but Papyrus was making it hard not too enjoy the direction this was going. 

“Sans is a little nervous still” he noted the way his eldest froze when his name was mentioned, stopping his attempts at escape completely “I want you to look at him, so he can see how much you’re enjoying this”

Papyrus nodded, adjusting himself with the help of the tentacles holding his arms until he was in a slightly more upright position. His eyes were fixed on his brother’s face when Gaster finally started to push inside his tight heat. It was a snug fit, but Papyrus showed no signs of discomfort as he cried out for more. Gaster let himself be lost to the sensations as he set up a gentle and experimental rhythm. It felt so much better than he could have ever imagined, and Papyrus seemed to be enjoying himself exponentially. He had almost forgotten about his eldest son until his ragged breaths became too loud to ignore.

It wasn’t that Sans was trying to struggle any more, not really. Just as instructed Papyrus had been watching him the whole time and Sans seemed to have started to crumble under the pressure. It was clear he was still wrestling with his inner demons, but with Papyrus’s attention it was clear which side was going to win. Especially when Papyrus started to moan his brother’s name. Deciding it was time for his eldest son to take a more active role in their fun Gaster willed the tentacle he’d had hovering outside of Sans’s shorts to delve inside. 

He wasn’t surprised when he found a hard, practically throbbing, cock inside. Hearing Sans hiss in pleasure was just as endearing as his brother’s building crescendo, but it was quickly followed with a choked groan as Sans realised what he had done. 

“what are you doing ‘dings-” Sans voice still carried the same malice even while his hips were eager to thrust into the coil he was creating around the smaller skeleton’s cock “this aint right he’s still-”

“He’s completely conscious, I snapped him out of the trance right before I penetrated him-” Gaster thrust the tentacle he had inside Papyrus in harder to prove his point while starting to jerk Sans off “If he was still under, he would only be crying out for me and not you as well”

Papyrus must have been listening to them even through his own noises as he chose that moment to practically scream “Please, Brother!” 

“you mean he really wants-” Gaster saw the moment the penny dropped for Sans, his whole skull blushing a bright blue as his cock started to leak in his hold“ oh fuckkkk” 

It was like a switch had been flipped for Sans as he arched into him desperately, never taking his eyes off Papyrus. The younger brother was affected by watching Sans more than the scientist could have anticipated, his pussy was becoming tighter and a small amount of liquid magic was dribbling onto the the floor. Flicking his own eyes between them both watching each other so intently made Gaster so happy he only realised he was making his own sounds when Sans shifted back against him.

The smaller skeletons body felt hot and inviting even through the chair as he bucked up into his tendrils. Gaster found himself wishing there wasn’t anything in between them and before he knew it his tentacles were unwrapping and picking up the smaller skeleton and placing him in his lap. Sans may have been a bit too old to sit in his father's lap under usual circumstances, and he was a little on the heavy side, but he just seemed to sink into the embrace like it was the most natural thing in the world. 

“so good, so hot” Sans had almost completely dropped his earlier worried as he started losing himself to his baser instincts “gaster i need- oh shit paps- you’re so fucking hot” 

With Papyrus snapped out of the trance he was even more influenced by the praise, writhing against his bonds and desperately trying to search for more stimulation. Gaster decided to reward his son for his compliance, stimulating every inch of magic flesh and speeding up his thrusts until Papyrus was shaking from the intensity “I Can’t Take It, It’s So Good! Make Me Cum Pleaase” 

Both Gaster and Sans cursed under their breath simultaneously before turning to look at each other. Gaster saw an idea flash across his son’s features before he felt teeth being pressed harshly against his own. Gaster choked in surprise, this wasn’t something he would have ever expected considering the circumstances but with Sans whimpering and grinding back into his lap it didn’t take him long to deepen this kiss. As their magic mixed Gaster felt a little light headed with so much stimulation. He had almost lost himself to the kiss when Papyrus pulled their attention back to where he was being fucked relentlessly. 

Gaster felt it before he heard his son toppling over the edge, the way his pussy clamped over the tendril inside him almost made him climax too. Gaster stilled all other movements bar the ones that were prolonging Papyrus’s pleasure, making sure to tighten his hold on the base of Sans’s cock. It earned him a whine of frustration from the skeleton in his lap, but he knew Sans will forgive him for the denial later. He knew cumming inside that sweet pussy would feel a million times better, and he didn’t want to deny either of his sons that experience any longer. The fact that he was unbelievable turned on at the prospect of watching them together was just an added bonus. 

Gaster eased up his thrusting in Papyrus, giving him a chance to catch his breath before slowly unfurling the tentacles holding Sans in his lap. 

“Go to him”

Sans practically jumped up when he was freed, but then he hesitated before making his way over to his still panting brother “what about you?”

Papyrus seemed to perk up a little upon hearing Sans’s question, looking at Gaster expectantly. Again, his boys had surprised him; here he was setting up their chance to be together at last, but they weren’t content to leave him in the sidelines. Even though arousal hung heavily in the air, Gaster was more than a little touched. 

“Oh my boys, I will enjoy watching this more than anything” He saw them both flush further at the prospect of being watched, but he could tell they welcomed the encouragement. Gaster was about to remove himself completely but he noted the flash of disappointment on both their faces when he went to retract the tentacles. He couldn’t help but hum in pleasure, it seemed his boys really did enjoy the pleasure his extra appendages could bring “I can keep them summoned if you wish” 

Sans flushed brightly before nodding his head, Papyrus on the other hand just moaned when he began stroking him with the tendrils again. Gaster moved his chair close as Sans moved in between his brothers legs, deciding that sitting to the side would give him the best view of their faces. Though he might not have been able to see them as intimately, seeing their expressions of pleasure was what he wanted to get off too. Focusing some of his magic to coalesce in his pelvis wasn’t an issue, but with how stimulated he already was it was no surprise that a thick tendril was the sight that greeted him when he unbuttoned his slacks. He thought about changing it but a soft whine from Papyrus drew his focus as he wrapped his hand around himself with a gasp. This form would be more than adequate. 

Sans was stood between his brother’s legs, the bed being just the right height for his still hard cock to gently press against Papyrus’s pussy as he leant in to kiss him. Papyrus mewled and returned the kiss with just as much passion, his now free arms gripping onto Sans feverishly. With the boundaries between them crumbling before his eyes Gaster noted just how well his boys fit together. The vision of orange and blue in front of him was almost poetic, but the flashes of darker magic reminded him how he was still very much entangled in their embrace. He planned on using that to prompt them to go further; he and Sans still needed released and he was sure Papyrus wouldn’t object about another climax either. 

He wrapped himself around them again slowly, careful to enhance their kiss rather than distract them from it. As well as stroking every inch of them he could reach Gaster slowly manipulated Sans’s cock until it was rubbing around Papyrus’s entrance. Both of his boys moaned at the feeling before drawing back from each other. 

It seemed like they both wanted to continue, but Sans brought a hand up to brush at his brothers face lightly “you sure you really want this paps?”

“I’m So Sure Sans, Please I Love You So Much I- Ah-!” 

Papyrus’s confession had been too much for his brother to take, he sank inside him in one movement before leaning in to kiss him desperately. Sans didn’t waste time in building up a fast pace, already far too worked up from what they had done previously. Papyrus didn’t seem to mind; he cried out for his brother on almost every thrust and it wasn’t long before he was begging for more. Gaster had been stroking himself idly, completely caught up in their display but the cries for more sprung him into action. He sped up his own hand and let his tentacles do what they wanted. He could feel himself wrapping around sensitive flesh, stimulating pleasure points, and smearing his own magic all over them both. He was so close, and he could tell that his sons weren’t far behind. 

Sans was the first to cum with a string of curses before growling and burying himself as deep as he could in Papyrus. Papyrus followed almost immediately when he felt his brother shooting his load inside him, over-stimulation causing his whole body to shake. Gaster ended up biting on his hand as he came all over himself, watching as the many tendrils covered his sons in sticky magical residue. It felt amazing, it really had been far too long since he had allowed himself to indulge in such pleasures. But more than that he was happy, his experiment had been a complete success and everyone involved was more than satisfied. 

At least that’s what he thought.

His climax had distracted him enough that he didn’t notice his boys had started to move against each other again. Sans was still buried inside his brother, but was now using his tongue to lick all over Papyrus’s chest where there was a large concentration of Gaster’s magic. Papyrus didn’t seem to mind, although he was sensitive he whimpered softly from the attention before leaning forward to kiss Sans again. The sight of his magic being shared between his sons was enough to make Gaster hard again. He wasn’t surprised, this whole situation was a testament to his narcissistic tendencies. 

It was a good job he had cleared their schedule for the next few days. Gaster smirked remembering what he filled the request under. 

‘Festive family fun’ still seemed appropriate.


End file.
